ML20006E675
| ML20006E675 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 02/16/1990 |
| From: | Shelton D TOLEDO EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 1757, NUDOCS 9002260202 | |
| Download: ML20006E675 (25) | |
Text
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m TOLEDO
%me EDISON A Camerur Energy Cm L
DONALD C. SHELTON
. Vre Prende4-Nelear I
(*******
Docket Number 50-346 H
License Number NPF-3 Serial Number 1757 i
February.16, 1990 l
n United States Nuclear Regulatory Commission
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Document Control Desk
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L Vashington, D. C.
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Subject:
Fire Protection-Changes from Previous Submittals in Fire Protection Compliance Approaches Gentlemen:
At the Fire Protection meeting with the Nuclear Regulatory Commission (NRC) held at Davis-Besse on October 4 and 5, 1989, Toledo Edison discussed a number q
i of issues.for which the approach being taken to achieve compliance with Appendix R had not been previously submitted or the approach utilized was different from information previously provided to the NRC by letter. The
-information provided in this letter falls into the following general categories:
Compliance approaches not previously submitted (Attachment 1)
Changes to Appendix R implementation approaches previously submitted (Attachment 2)
Changes to License Amendment Number 18 SER compliance approach 4
(Attachment 3)
P The Toledo Edison approaches for analyzing the effects of multiple high
.impendance faults and analyzing room heatup as the basis for not protecting i
selected HVAC equipment are provided in separate attachments (Attachments 4 and 5).
All references to the Compliance Assessment Report (CARP) and Fire Hazards Analysis Report (FHAR) in this letter pertain to CARP Revision 5 and FHAR Revision 11 which were transmitted to the NRC by Toledo Edison letter Serial Number 1746 dated December 18, 1989.
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.Because the Fire Protection SER now being prepared vill supplement and amend the Fire Protection SER issued by NRC letter dated' July 26, 1979 as part of License Amendment Number 18, revised information pertaining to this earlier SER'is provided in a separate attachment. This approach vill facilitate its incorporation into the SER. The items in Attachment 3 have been previously discussed with the NRC during the October 4-5, 1989 meeting.
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. THE TOLEDO EDISON COMPANY EDISON PLAZA 300 MADISON AVENUE TOLEDO, OHIO 43652
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Docket Number 50-346 i
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Page 2 If you have any quer.tions concerning this matter, please contact Mr. R.2V. Schrauder, Manager - Nuclear Licensing at (419) 249-2366.
Very truly ' yours, j
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cc P. M. Byron, DB-1 NRC Senior Resident Inspector A. B.' Davis,' Regional Administrator, NRC Region III D. J. Kubicki, NRC/NRR Staff Reviewer i
T. V. Vambach, DB-1 NRC Senior Project Manager j
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Dock;t Number 50-346 4
Licens) Number NPF-3 i
- Serial Number 1757 l
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Compliance Approaches Not Previously Submitted
'1.
Essential Inverter Modifications i
There are four essential inverters (YVt, YV2, YV3, YV4) that vere analyzed for the Appendix R Compliance Assessment Report (CARP) and determined not to be coordinated (i.e., a single fault could result in the inverter being lost due to input fuse failure).
A modification to replace the inverters has been generated and the new inverter design vill ensure that coordination for i
a single fault is maintained. Two of the inverters vill be replaced by the end of the_ sixth refueling outage. The remaining two inverters are j
scheduled to be replaced during the seventh refueling outage.
During the sixth refueling outage's modification to the remaining two original i
inverters vill be made to allow a manual transfer to a redundant essential power supply should the inverter input fuse fail due to a fault resulting from a fire.- This configuration and the procedure revision for the required manual action vill be completed prior to the end of the sixth refueling i
outage and vill remain in place until the remaining two inverters are replaced during the seventh refueling outage.
2.
Letdown Path Protection As part of the revised safe shutdown methodology, a Reactor Coolant System (RCS) letdown flow path vill be required to be established following a fire.
l The letdown path has been included to ensure that adequate shutdown margin can be maintained during cooldown of the RCS. Revision 5-of the CARP includes this revised safe shutdown methodology, and CARP Table 1-1 reflects i'
non-compliance with Appendix R until the safe shutdown procedures are revised. As part of the process to reestablish the RCS letdown flow path, some fire areas contain motor or air operated valves which could be exposed to a fire in the area and require manual repositioning. Additional _
information on the valves and fire areas involved is provided in item 4 of to this letter. The revisions to the safe shutdown procedures reflecting the requirement to establish a letdown path vill be completed by the end of the sixth refueling outage.
3.
Motor Operated Valves (MOV)
In the notes for CARP Section 4 concerning associated circuits, circuits for HOVs are considered as not posing an associated circuits concern. These MOVs are not high/ low pressure interface valves.. At least two faults vould be required for these valves to operate and concurrently result in an associated circuit concern. Thus, based on the guidelines of Generic Letter i
(GL) 86-10, the probability of multiple faults is considered sufficiently
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lov as to not require further evaluation. As a precautionary measure, the current " Serious Station Fire" procedure includes guidelines for tripping the breakers for valves with circuits located within the fire area and for the operators to manually operate specified valves locally if necessary.
Based on GL 86-10 guidelines for valves that are not high-low pressure interface valves, these precautionary measures vill be deleted from the
" Serious Station Fire" procedure. This change vill simplify and streamline the procedure and reduce operator burden during use of the procedure.
f I Dockat Number 50-346 g'
,Lic:ns3 Number NPF-3 l
Serial Number 1757 i
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-Page 1 Changes to Previously Submitted Compliance Approaches 1.
Commitment: In the response to Question No. 42 of Serial 1456 dated January 6, 1988, Toledo Edison committed to provide the capability of an onsite source of fuel oil to compensate for the loss of the redundant fuel oil transfer pumps which supply the emergency diesel generators (EDG). The i
ensite capability will be provided by adding a portable fuel oil i
transfer pump and temporary connection to transfer fuel oil from the Diesel Oil Storage Tank to the EDG day tank. The necessary equipment vill be connected when required utilizing a repair procedure.
3 Revised Commitment: Toledo Edison is maintaining the commitment to provide the capability of an onsite source of fuel oil. The EDG Day Tanks are l
normally. supplied with fuel oil from the EDG Fuel Oil Storage tanks.
For a fire at the EDG Fuel Oil Storage Tank area which is postulated to result in the failure of the transfer pumps for both EDGs, an EDG Day Tank vill be supplied with fuel oil from the Diessl Oil Storage Tank.
The supply capability vill be provided by the installation of a flexible hose connection between existing piping of the EDG Day Tank and the Main Diesel 011 Storage Tank transfer pump. This vill provide the capability for the transfer pump, which is diesel generator power backed, to pump fuel oil from the Diesel Oil Storage Tank to the EDG Day Tank. The flexible hose connections will be installed and the hose available but not connected by the end of the sixth refueling outage. The repair
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procedure to connect the hose and transfer fuel oil from the Diesel 011 Storage Tank vill be completed by the end of the sixth refueling outage.
l 2.-
Commitment: In the response to Question No. 41 of Serial 1456 dated January 6, 1988, Toledo Edison committed to install ground-fault protection to preclude multiple high impedance faults or perform manual operator actions to isolate the associated circuits of concern at the Motor Control Center (MCC) through selected tripping of the busses.
I Revised Commitment: Toledo Edison has performed an analysis which shows I
that. multiple high impedance faults caused by a fire do not cause a loss of safe shutdown capability. Therefore, no ground-fault protection is required to resolve the issue of multiple high impedance faults.
, provides an overview of the calculations to support this conclusion.
l 3.
Commitment:
In the response to Question 24 of Serial 1471 dated February 8, 1988, Toledo Edison committed to implement any physical modifications or procedure revisions to provide Reactor Coolant Pump (RCP) seal cooling f.
by the sixth refueling outage.
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'. Docket Number 50-346 Licens) Number NPF ' Serial Number 1757 Page 2 Revised Commitment: Toledo Edison is replacing the existing RCP seals with a newly designed RCP seal.
Based on test data, integrity of the new seal is maintained without seal cooling for eight hours.
After eight hours, RCP seal cooling and seal return vill be reestablished. As part i
of the process of providing RCP seal cooling and seal return, some fire areas contain motor or air operated valves which could be exposed to a i
fire in the area,and require manual repositioning. Additional detailed I
information is provided in Item 4 of Attachment 2 of this letter. The
-seal changeout and the procedure revision to reestablish RCP seal i
cooling and seal return within eight hours vill be completed by the end 1
of the sixth refueling outage.
4.
Commitment: In the response to Question 28 of Serial 1361 dated May 27, j
1987. Toledo Edison described the motor or air operated valves which could be exposed to a fire and later require manual repositioning.
.l Valves DH 2734, Dil07A, CF01A, CF01B, DH1517, SV1399, SV630, SV631 and SV632 were covered by the response to the question.
Revised Commitment: Based on further review, the list of valves has been modified.
Specifically, two additional motor operated valves (SV 1367 and SV 1368) have been added and one motor operated valve (SV 1399) has I
been deleted from the list.
In addition, the Main Steam Code Safety I
Valves and Atmospheric Vent Valves have been included to reflect that l
their post-fire operability has been reviewed and found to be unaffected by a fire in their area, even though the Main Steam Code Safety Valves do not involve operator action.
As discussed in Item 2, Attachment I and Item 3, Attachment 2, the list of valves has been expanded to reflect the reestablishment of the letdown path and RCP seal cooling and seal return. The following is the revised response to Question 28.
There are a number of fire areas in which there are motor or air operated valves which could be exposed to a fire in the area and require repositioning to achieve safe shutdown.
Appropriate action vould be taken by the Fire Brigade and Operations personnel to extinguish the fire and to manually reposition the safe shutdown valves.
Table 2-1 lists the fire areas, valves, and combustible loadings for achieving safe shutdown but excludes the valves required for reestablishing the-4 letdown path and/or RCP seal cooling and seal return. Table 2-2 lists the fire areas, valves,-combustible loadings and function to reestablish the letdown path and/or RCP seal cooling and seal return.
Tables 2-1 and 2-2 include motor operated and pneumatically operated valves which are required to be manually operated and code safety valves that must operate following fires in the area. Both motor-operated and pneumatic valve types can be manually operated via the valve handvheel operators which are strictly mechanical.
Table 2-1 also includes the Mein Steam Code Safety Valves for completeness, even though no operator l
action is required for post-fire operation.
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l l' Docket Number 50-346-Licens] Number NPF-3
' Serial Number 1757 I
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L Table 2-1 1
Valves Required to Operate after a Fire in the Aree (Non-Pover Operation)
Combustible Fire Valve Loading
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Area ID No.
Description (BTU /sq. ft.)
AB DH 2734 Decay Heat Pump 2 BVST Suction Valve 6,900 AC DH 07A BVST Isolation Valve 700 D
CF01A&B Core Flood Isolation Valves 16,000 J
DB DH 1517 DHR Suction Line 1 Valve 15,900 DH SP17Al Main Steam Code Safety Valves 600 through t
SP17A9 DH SP17B1 Main Steam Code Safety Valves 600 through SP17B9 DH*/EE ICS11A Main Steam Line Atmospheric Vent Valve 600/20,600 DH*/EE ICS11B Main Steam Line Atmospheric Vent Valve 600/20,600 i
DJ SV 1367 Containment Air Cooler Inlet Iso Valve 46,700 DJ SV 1368 Containment Air Cooler Inlet Iso Valve 46,700 II-SV 630 TPCW Heat Exchanger Outlet Iso Valve 18,400 II SV 631 TPCW Heat Exchanger Outlet Iso Valve 18,400 II SV 632 TPCV Heat Exchanger Outlet Iso Valve 18,400
- In fire area DH, these valves are manually repositioned by personnel standing outside the fire area by remote mechanical operators.
i Therefore, entry into the area of the fire is not required for manual operation.
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Docket Number 50-316
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,Licens] Number NPF-3 l
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Serial Number 1757 l
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Table 2-2 L
Valves for RCP Seal Cooling, Seal Return, and RCS Letdown Path that May Require Manual Operation r
Valve Combustible Fire Function Valve Loading Area (notes belov) ID No.
Description (Btu /sq. ft.)
A 2,4 VC.1743
- Clean Vaste Receiver Tank 1-1 12,200 r
Inlet Flow Control Valve A
2,4 VC 1747
- Clean Vaste Receiver Tank 1-2 12,200 Inlet F?ov Control Valve D
4 CC 1409
- RC Letdown Cooler 1 CCV 16,000 Inlet Valve 1
D 4
CC 1410
- RC Letdown Cooler 2 CCV 16,000 Inlet Valve 3
D 4
MU 01A
- Letdown Cooler 1 Inlet 16,000 Valve D
4 MU 01B
- Letdown Cooler 2 Inlet 16,000 Valve D
4 MU 02A Letdown Cooler 1 Outlet 16,000 Isolation Valve D
'4 HU 02B Letdown Cooler 2 Outlet 16,000 Isolation Valve DC 2
MU 38 RCP Seal Return Isolation 5,400 l
Valve
, DE -
1 HU 19 Seal Injection Inlet Isolation 9,100 Valve DJ 3,4 CC 1407B CCV Isolation Valve from 46,700 containment motor operated source DJ 3,4 CC 1411B CCV Isolation Valve to 46,700 containment motor operated source G
2 CC 2645
- CCV from Auxiliary Building 12,300 to Line 1 Isolation Valve G
2 CC 2649
- CC from Auxiliary Building 12,300 to Line 2 Isolation Valve G
2,4 VC 3560 Degasifier Bypass Valve 12,300
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Serial-Number:1757:
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Table 2-2 (continced)
Valve Combustible Fire Function Valve Loading Area (notes belovl ID No.
Description (Btu /sq. ft.)
G' 2,4 VC 1453 Clean vaste Primary 12,300 Demineralizer Inlet Valve 1
2,4 MU 10A
- Purification Demineralizer 1-1 2,600 Inlet Valve p
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2,4 HU 10B
- Purification Demineralizer 1-2 2,600.
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Inlet Valve I
2,4 MB 1903
- Purification Demineralizer 1-3 2,600' Inlet Valve l
I 2,4 HU 11 Letdown to Radvaste 2,600 i
a Three-Vay-Valve i
J T-2,3,4 CC 5095
- CCW Line 1 Discharge Isolation 1800 Valve j
T 2,3,4 CC 5096
- CCW Line 2 Discharge Isolation 1800 Valve-
.T 3,4 CC 5097
- CCW Line 1 Return 1800 i
Isolation Valve.
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3,4 CC 5098
- CCV Line 2 Return 1800 1
Isolation Valve
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CC 1495 CCV to Nonessential Inlet 39,600 Isolation Valve j
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- -.These valves are for redundant flow paths for this fire area and either i
valve (s) may be used, f
Notes:
- 1. Valve (s) required to establish RCP Seal Injection j
- 2. Valve (s) required to establish RCP Seal Return
- 4. Valve (s) required to establish RCS Letdown Flow Path y
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o The fire-induced failure mechanism which could affect manual operation
-of these valves is binding due to either thermal expansion or lubrication degradation. This failure mechanism would not occur to the, E
valves listed in Tables 2-1 and 2-2 based on the. combustible loading for the fire areas indicated. The full BTU energy content of the combustibles vould not be transmitted to the valve operators since the combustibles in these fire areas are mainly combinations of cables in 1
solid bottom cable trays with Kaovool on top, enclosed charcoal filters, or enclosed grease and oil.
Consequently the motor and air driven valve operators listed in Tables 2-1 and 2-2 would not be mechanically impaired by a fire in such a j
manner to prevent subsequent manual handwheel operation of the valves, r
The redundant Main Steam Line Atmospheric Vent Valves ICS11A and ICS11B are located in Fire Area DH and the associated manual operators are located in Fire Area EE.-
In Fire Area DH, the valves are separated by 1
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over 200 feet with negligible combustible loading.
In Fire Area EE, the manual valve operators are separated by over 200 feet with lov combustible loading with adequate time to extinguish the fire and operate the valves manually.
In addition one of the manual valve P
operators is located in Room 501 and is protected by an automatic sprinkler system.
i The Main ~ Steam Code Safety Valves, SP17Al through SP17A9 and SPl7B1 through SP17B9 are also located in Fire Area DH and must be operable after a fire in that area for secondary side heat removal in'the hot-standby condition. The Main Steam Code Safety Valves are spring loaded pressure relief valves which are assumed to remain operational during and after a fire.
Based on the lov overall' quantity of combustible L
loading of 600 BTU /ft*, no credible means of producing significant fire i
L damage which could adversely affect valve operation exists.
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Valve SV 1399 is redundant to SV 630, 631 and 632. These redundant.
P valves are located in separate rooms 53 and 334 respectively in Fire Area II.
Room 53 is at elevation.565 feet'and' connected to the-remainder of Fire Area II (i.e., Room 334) by a tunnel over 200 feet long. Valve SV-1399 can be operated from the Control Room for a fire in Room 334.- If there is a fire in Room 53, then manual action to-operate SV 630, 631 and 632 can be performed.
5.
Consitment: In the response to Question 18 of Serial 1361 dated May 27, 1987, Toledo Edison committed to modify the Control Room console to indicate both local panel and affected fire detection zone for those fire areas identified in the FHAR. The revisions were scheduled to be completed by the end of the sixth refueling outage.
Revised Commitment: -Toledo Edison is re-evaluating the scope of the original commitment to determine the best approach to modify-the Control Room console. Toledo Edison has rescheduled the completion of the presently undefined Control Room console modification to the eighth refueling outage. As stated in the original letter, "The
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- Seria'l Number 1757.
l Page 7 revisions to the console are considered enhancements and are not necessary to satisfy Appendix A to BTP APCSB 9.5-1 or 10CFR50, Appendix R"._~ Based on the fact that the modification does not Affect system operability and is not required to satisfy a regulatory requirement, c
-deferral to the eighth refueling outage is in accordance with the schedule provided in the December 2, 1988 letter (Serial Number 1595).
6.
Commitment: In the response to Question 6 of Serial 1396 dated July 30, I
1987, To'ledo Edison committed to provide isolation capabilities between the sprinklers and hose stations for nine rooms. The design changes and s
the procedure changes to designate the alternative hose stations were scheduled to be implemented by the end of the sixth refueling outage.
Revised Commitment: Toledo Edison has rescheduled the completion of the-modification to provide the isolation capabilities to the eighth refueling outage. The modification is an enhancement to improve the maintenance capability and does not affect system operability. The modification has been deferred until the eighth refueling outage in ~
accordance with the schedule provided-in the December 2, 1988 letter (Serial Number 1595).
7.
Commitment: In the CARP Section 4 notes for Fire Areas DD/FF, A, DB, HA, U, and V, Toledo Edison stated that the Containment Emergency Sump Isolation Valves DH09A and DH09B could spuriously open with unacceptable results. An isolation svitch in the circuit scheme for valves DH09A and DH09B was to be installed such that fire damage cannot spuriously open the valves.
Revised Commitment: Toledo Edison has determined that the original modification is no longer required to resolve the spurious operation concern.
Instead of the modification, the breakers (BF1142 and BE1112) for valves DH09A and DH09B vill be left normally open to prevent spurious valve opening as a result of a fire. This action to open the breakers vill be completed by the end of the sixth refueling outage.
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'more detailed discussion of the modification and the procedure changes is provided in a Toledo Edison letter to the NRC, (Serial 1744, dated 1/9/90).
8.
Commitment: In.the CARP Section 4, Note 10 for Fire Area II (Room 53),
Toledo _ Edison stated that the circuits for Service Water Pumps 1 and 3 are currently protected with a one-hour fire barrier.
Since detection and automatic suppression systems presently exist in Room 53, these t
circuits are currently in compliance with Appendix R,Section III.G.2.
In Serial 1497 dated May 23, 1988, Toledo Edison committed to upgrade the sprinkler system in Room 53.
Revised Commitment: Toledo Edison has re-evaluated the method of Appendix R compliance in Room 53 and determined that an acceptable method of Appendix R compliance for Room 53 is to provide a three hour fire barrier without requiring the detection system and the upgrades to the sprinkler system. This upgrade to a three hour fire barrier for the circuits for Service Water Pumps 1 and 3 listed above vill be completed by the end of the sixth refueling outage.
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'. *DockStlNuiber 50-346 f
, Lic:nsa Nu2b3r NPF-3
' Serial' Number 1757 l
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Commitment: Toledo Edison committed to install and/or modify the emergency lighting. system'as described in CARP Table 6-3 " Emergency Lighting
' System Modifications Identified"_and CARP Table 6-6 " Summary of Recommendations for a Serious Station Fire".-
Also, a note to Table 6-6 stated that two rooms required further evaluation.
Revised Commitment:
Emergency lighting has been or vill be installed in the-areas as described in CARP Tables 6-3 and 6-6 except for 3 rooms (250, 705 and 706).- Rooms 250, 705 and 706 no longer require emergency-i, lighting based on the latest valkdown of the safe shutdown procedure.
The two rooms containing the diesel air compressor system listed in the Note to CARP Table 6-6 have been evaluated for manual action. No manual actions are required in these two areas; thus no additional emergency-lighting is required.
See Item 10 Attachment 2 for additional details.
The emergency lighting required to support the safe shutdown procedures.
vill be completed by the end of the sixth refueling outage.
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- 10. Commitment:
In CARP Table 6-2 " Emergency Lighting Evaluation for a Fire in the Control Room or' Cable Spreading Room", Toledo Edison committed to relocate the diesel air compressor and associated valves tr. resolve lighting concerns.
l Revised Commitment: Toledo Edison has determined that the air system is not necessary to achieve safe shutdown. Therefore, there is no need to i
relocate the diesel air' compressor and associated valves to resolve lighting concerns.
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- 11. Commitment: In the CARP Section 4 notes for various fire areas, Toledo I
Edison stated that the associated circuits of concern vould be resolved by installation.of ground fault' protection at the breakers.
Revised Commitment: Toledo Edison has re-evaluated the method-of providing:
-ground fault protection at the breakers and determined that the most.
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effective method is to change the solidly grounded 480V Class IEcbus to a high resistance grounding system to preclude a ground from_ tripping a y
breaker.
Based on an analysis of the buses and loads which are required for safe shutdown, several breakers to cascaded McC's vill be removed to-achieve the-desired-breaker coordination. These modifications vill be completed by the end of the sixth refueling outage.
- 12. Commitment: In the CARP Section 4, Note 4 for Fire Area T (CCV Heat Exchanger and Pump Room 320), Toledo Edison stated isolation devices
- vill be installed for both trains of 125V DC circuits to preclude the loss of 125V DC control power to the flow switches for the three Component Cooling Water Pumps.
Revised Commitment: Toledo Edison has re-evaluated the method of Appendix R compliance for the 125V DC circuits and determined that the most effective method is to wrap the circuits as well as the switches themselves with one-hour fire barriers. The fire area contains area vide suppression and detection and with the one-hour fire wrap satisfies es
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,Lic nse Nurb2r NPF Serial Number 1757
- a Page 9 the 10CFR50 Appendix R' requirements. The one hour fire wrap of the circuits and the switches vill be completed by-the end of the sixth refueling outage.
- 13. Commitment: In the CARP Section 4, Note 73 for Fire Areas DD/FF (Cable Spreading Room 422A/ Control Room Complex), Toledo Edison stated that a Source Range Flux Monitor vill be installed at the Auxiliary Shutdown
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panel.-
Revised Commitment: Toledo Edison has re-evaluated the method of providing source range flux monitoring and determined that an acceptable method is to provide Source Range Flux Monitors in the two electrical penetration-1 rooms (402 and 427) where the circuits exit the containment. The reading of a Source Range Flux Monitor in either electrical penetration room has been evaluated as part of the time line for manual actions and is acceptable'from a time and manpower standpoint..These Source Range Flu'x Monitors vill be installed and the procedure revised for their use by the end of the sixth refueling outage.
- 14. Commitment: In the CARP Section 4, Note 38 for Fire Area DD/FF 4 Cable Spreading Room 422A/ Control Room Complex) Toledo Edison stated that the
= power supply circuit to the ammeter vill be isolated by de-energizing
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.the circuit by means of a shorting bar at the 4.16KV AC Switchgear Bus C1.
Revised Commitment: Toledo Edison has re-evaluated the circuit of concern and determined that the power supply to the ammeter on the 13.8KV bus
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vill'be de-energized by a manual action following a serious fire in fire 1:
area'DD/FF. Thus, the loss of this circuit would not pose a concern and L
the manual action as described in the CARP is no longer required.
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- 15. Commitment: In CARP Section 4, Note.2 for Fire Areas-D (Containment).and DA-(Annulus) Toledo Edison stated the circuits for~ Containment Air Coolers
_(CAC) Fans 1, 2, and 3' vill be separated with radiant energy shields.
In CARP Section 4 Note.3 for Fire Area DF, Toledo Edison stated'that-the l
circuits for CAC Fan 3 (i.e., the sving train of equipment) vill be l
h protected with a one-hour barrier.
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Revised Commitment: Toledo Edison has determined that the protection of only one train of Containment Air Cooler' Fans is required to satisfy-Appendix R requirements. Therefore, only one train of CAC Fans vill be l
protected in a particular fire area.
As required by Appendix R, this 3
protection vill be provided by a radiant energy shield in the Containment and Annulus and with an one-hour barrict and suppression and detection'or a three-hour barrier in the Auxiliary Building.
This approach of protecting only one train of a system to satisfy Appendix R requirements vill be applied to other systems with sving
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components.
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Serial Number 1757
Attachment:
2:
L Page 10-16.- Commitments In the CARP Section 4, Note 33 for Fire Area DJ, Toledo Edison
-stated that the circuits for Service Vater valves SW1367 and SV1368
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vould be provided with isolation switches to resolve the spurious action
.l concern.
Revised Commitment: Toledo Edison has determined that the modification is no. longer required to resolve the spurious action concern. There is sufficient time available to manually operate these valves for a fire in the area.
As stated in Attachment 2, Item 4 of this letter, SW1367 and SW1368 vill ~ remain available for manual repositioning following the extinguishing of the fire. Thus, the. isolation switches are no longer-required.
- 17. Commitment: In CARP Section 4, Notes 7 and 8 for Fire Area 0 (High Voltage Switchgear-Room 232), Note 6 for Fire. Area X (Lov Voltage Switchgear
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Room 428), and Note 46 for Fire Area DD (Cable Spreading Room 422A),
Toledo Edison stated that the damage to HVAC electrical circuits results in-the malfunction of dampers and vill require a three-hour wrap or manutil action to provide ventilation in Rooms 429 and 4298.
Revised _ Commitment: Toledo Edison has re-evaluated the commitment and has performed a calculation that determined the temperature transients following a fire vill not be detrimental to plant equipment.in Rooms-429 and.429B (Lov Voltage Switchgear and Battery Rooms). Therefore, the HVAC electrical circuits are not required to be wrapped..The manual action is to-provide ventilation in Room 429. The manual actions will be proceduralized by the end of the sixth refueling outage.
Attachment
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5 provides an overview of the calculation to support the conclusions..
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,, Licenza Nu;ber NPF-3 Serial Number 1757-Page_1 Changes to License Amendment Number 18 SER Compliance Approaches 1.
Commitment: The Safety Evaluation Report (SER) Table 1 Item B.1 required an additional hand held-portable fire extinguisher to be added in the No.
3 Hechanical Penetration Room 303.
Revised Commitment: A National Fire Protection Association (NFPA)-10 t
Standard reviev was performed for Room 303 and determined that the currently installed extinguisher is sufficient. Therefore, an additional: extinguisher is not required in Room 303.
2.
Commitment: The SER Table 1 Item B.1 required an additional hand held e
portable fire extinguisher to be added in Maintenance Room 320.
Revised Commitment: A NFPA-10 Standard review was performed for Room 320 and determined that the currently installed extinguisher is-sufficient. Therefore, an additional extinguisher is not required in-Room 320.
3.
Commitment:
SER Table 1 Item B.2.A required ten vet pipe sprinkler systems to be equipped with quick response type sprinklers.
Revised Commitment: The existing type sprinklers,'except for Service Vater-Valve Room 53, vill be replaced with sprinklers in accordance with NFPA-13 standard requirements. As stated in Attachment 2 Item'8 of this-letter, upgrades to the sprinkler system in Room 53 are no longer required. The sprinkler upgrades vill be completed on the schedule as stated in the-Toledo Edison letter dated December 2,-1988 (Serial No.
_1595).
- 4.. Commitments: The SER Table 1 Item B.2.A required a vet pipe sprinkler system in Service Water Valve Room 53. Additionally, the sprinkler and
' detection systems were required to satisfy Appendix R requirements since a one-hour fire vrap was installed in the room to protect required circuits.
Revised Commitment: As stated.in Attachment 2, Item 8 of this letter,_the one-hour fire barrier is being upgraded to a three-hour fire barrier.
-Upon completion of the upgrade to a three-hour barrier, the suppression and detection systems vill no longer be required to satisfy Appendix R requirements. The upgrade to a three-hour fire barrier vill be completed by the end of the sixth refueling outage.
5.
Commitment: SER Table 1 Item B.2.B required the vet pipe sprinkler system in the Cable Spread-Room 422A to be equipped with thermal actuated type waterspray nozzles.
3 L
Revised commitment: The water spray nozzles in the Cable Spread Room 422A l
vill be replaced with sprinklers in accordance with NFPA-13 requirements. The sprinkler upgrades vill be completed by the end of o
_the sixth refueling outage.
1 x
Dock 3t Nu b:;r 50-346 -
in Lic ns2 Nulber NPF-3
' Serial Number 1757-C Page 2 6.' Commitment: The SER Table 1 Item B.7.B required Door 508 in the Control.
1 Room Complex to be 1% hour fire rated.
. Revised ~ Commitment: The Fire Hazard Analysis. Report Section 5.FF for the Control Room Complex was revised to redefine the fire rated boundaryf g
such that the vall containing Door 508 is no longer part of the Control Room Complex fire boundary.- Therefore, Door 508 does not require a 1% hour fire rating.
.7. Consitment: The SER Table 1 Item B.9 required spray-on type fire proofing.
-of supports.for four horizontal cable trays penetrating the three-hour barrier at column line 0-F on elevation 602'-0".
Revised Commitment: Instead of using a spray-on fire proofing, additional sprinklers in accordance with NFPA-13 Standard requirements have been installed to protect the supports and to prevent the potential associated' degradation of the penetration seal between the Turbine Building and the Cable Spreading Room.
In addition, the location of the cable' tray supports at column line 0-F and 602'-0" was incorrectly 1
identifie& and the correct location is column line 9-F and 603'-0".
?
1 8.
Consitzents-The SER Table 1 Item B.9 required spray-on type fire proofing to supporting structural steel in mechanical and electrical-penetration rooms (Rooms 208, 236, 303, 314, 402 and 427).
Revised Commitment: Instead of using a spray-on fire proofing, sprinklers have been installed in these rooms. The NRC accepted the use of the.
s sprinklers in lieu of a spray-on fire proofing-in a letter dated July 17, 1980, but inadvertently omitted Room 314 from the approval letter.
The sprinklers in Rooms 208, 236, 303, 314, 402 and 427 adequately i
protect the supporting structural steel.
9.
Commitment: The SER Table 1 Item 9B required spray-on type-fire proofing for supporting structural steel in the Turbine Building as determined by the Turbine Building Thermal Expansion Analysis.
1 Revised' Commitment: The Turbine Building Thermal Expansion Analysis.
concluded that sprinkler systems-vould provide an acceptable means of controlling a postulated fire and' reducing the potential for fire damage. This approach was provided to the NRC by a February 28, 1979 letter (Serial No. 486), Sprinklers were provided in the Turbine
.j Building Heater Bays (FSA-3501, 4501, 5501, 6501, 7501); Turbine Building Heater. Bay Roof Truss (FSA-7502); Turbine Building Basement, Mezzanine, and Operating Floor (FSA-4105);; Turbine Building Roof Train 4
{
Bay (FSA-5106); and Turbine Building Het Lab (FSA-5731).
Based on J
further evaluation, the sprinklers in the Turbine Building Roof Train Bay (FSA-5106) and the Turbine Building Het Lab (FSA-5731) are not i
required to protect the required structural steel in the Turbine Building..Also FSA-7501 and 7502 are being combined into a single system (FSA-7501) as part of the NFPA-13 standard upgrades.
Therefore, only the sprinklers in the Turbine Building Heater Bays (FSA-3501, 4501, 5501, 6501 and 7501) and the Turbine Building
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DockOt Nu ber 50-346
'Licenti Nu;b;r NPF Y
'lSerial Number 1757L Page 3; x
Basement, Hezzanine, and Operating Floor-(FSA-4105) protect the supporting Structural Steel in the Turbine Building.
~
- 10. Commitment: The SER Table 1 Item 8.10.3 required the installation of'an additional area type fire detector in Demineralizer Room 233.
Revised Commitment: A review of Room.233 determined that a detector was not
~
required due to the minimal fire loading (400 BTU /ft') and no safe shutdown cables were routed in the room. The room is inaccessible except through shield plugs from the room above.
Therefore, a detector is not required in Room 233.
- 11. Commitment: The SER Table 1 Item B.10.2 required the installation ~of additional area type detection in Fuel Handling Area Room 300.
Local detection vas provided in Room 300.
Revised Commitments- ' Additional area detection vill be added by the end of.
seventh refueling outage. In Licensee Event Report 86-030 Revision 1 dated March 23,-1988 Toledo Edison committed to install the area detection by the end of the sixth refueling outage.
Since the detectors are not required to resolve an Appendix R concern, the detectors will be installed by the end of the seventh refueling outage. This schedule is consistent with the Toledo Edison schedule L
letter dated. December 2, 1988 (Serial Number 1595).
- 12. Commitment: The SER Table 1 Item B.10.2 required the installation of in-tray,. linear type, thermal sensing fire detection inside'all the cable trays in the Cable Spreading Room 422A.
Revised Commitment: Cable Spreading Room 422A contains area ionization detectors that are being upgraded to resolve the NFPA-72E Standard deficiencies. Based on the Cable' Spreading Room construction of a l,
ceiling approximately 8 feet high and the upgrade to resolve the NFPA-72E Standard deficiencies, the area ionization detectors provide adequate detection' capability and the in-tray linear detectors are no
?
longer required. The detector upgrades will be completed by.the end of the sixth refueling outage.
- 13. Commitment: The SER Table 1 Item B.12 required the installation of 8-hour emergency battery pack lights in Passage 241.
p Revised Commitment: In 1987, a lighting unit was installed in Passage 241.
The power to this lighting unit is supplied from a battery unit in l~
Passage 227. -Therefore, this SER requirement is considered to be met.
- 14. Commitment: 'The SER Table 1-Item B.12 required the. installation of 8-hour emergency battery pack lights in Makeup Pump Room 225.
Revised Commitment: Instead of installing the lights in Room 225, the emergency battery pack lights were installed in the Vestibule (Room 226A) with a light directed into Room 225 to provide illumination for access and egress in Room 225. The lighting from Room 226A is l
(,
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?.o Dockst Nu;b;r.50-346-Licins3 Nurbar NPF-3 i
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' Attachment'3'
+
Page.4 continuous with no door or other intervening objects that could block M
the light. This SER commitment is considered to be met.
- 15. Commit' ment: The SER Table 1 Item B.13 required the installation of a g
.one-half hour fire rated barrier (Kaovool) in Service Water Valve Room
'53 around the power and control circuits for Service Water Valves (SV 2930, SV.2931) located in the Service Vater discharge ^ header.
Revised Commitment: -CARP Section 4 Note 12 for Fire Area II (Room 53)
(
states that.one of the four Service-Vater discharge valves (SV.2929 i
through SV 2932) is normally open and depovered-(controlled.
1
-administratively) to ensure Service Water discharge is available'for a f/ -
fire in the area. Therefore, the one-half hour fire rated barrier-(Kaovool) is no longer required.
3
- 16. Commitment: The SER Table 1 Item B.13 required a one-half hour rated 1
. barrier (Kaovool) in Passage 227 around the entire circuits for Train 1-Auxiliary Feedvater Pump suction valve FW 786, and interlock to i
Service Water valve SV 1382..
Revised Commitments.-CARP Section.4 for Fire Area G (Passage 227) states that Train 2 equipment is assured available for safe shutdown. Valves
-i SW 1382 and FV 786 are Train 1 valves and the Train 2 equivalent valves are not contained in fire area G.'
Therefore, the one-half hour fire rated barrier (Kaovool) is no longer required.
t
- 17. Commitment: The SER Table.1 Item B.13 required a' one-half hour rated barrier (Kaovool) in-Passage 209 around the circuits for the Borated Water Storage Tank (BUST) level ~ instrumentation, Makeup Pump No. 2, and Train 2 BVST outlet valve (DH07A).
i 1
- Revised Commitment: CARP Section 4 Note 19 for Fire Area G (Passage 209)
+
L states that the'High Pressure Injection (HPI) System is the system that is assured for Reactor Coolant System' Injection'(inventory and-L reactivity control) for safe shutdown for a fire in that fire-area.
l The Makeup System (i.e., Makeup Pump No. 2) serves as a redundant system to;the HPI and is not required to assure safe shutdown in fire i
area G.
CARP Section 4 Note 4 for fire area G (Passage 209) states that there
~
.is ample time available to manually open the Train 2 BVST. outlet valve Lq (DH07A) in Fire Area AC for a fire in Fire Area G to ensure f
availability for safe shutdown.
For the Fire Area G (Passage 209) safe shutdova analysis, the HPI pumps take suction from the BWST to maintain the water inventory in the Reactor Coolant System.
Due to the large BVST volume (Technical Specification minimum of 482,778 gallons) and the limited water volume required to achieve cold shutdown, it is not necessary to monitor the l
BVST water level to ensure that there is adequate BVST vater to
-(
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.l
" Lic:nsa Nu:bar NPF-3 Serial' Number 1757
' Attachment'3'
~Page 5 achieve cold shutdown.- Additionally as described in Attachemnt 2 Item 7, the' breakers (BF 1142 and BE 1112) for. valves DH09A and DH09B are 1 tripped open to prevent spurious valve opening as a result of a fire (i.e., inadvertent drainage of the BVST). Therefore, the one-half hour. fire rated barrier-(Kaovool) is.no longer required.
- 18. Commitment: The SER Table 1 Item B.13' required.the installation of.a en one-half hour fire rated barrier (Kaovool) in. Passage and Hatch Areas 310 and 313 around the. circuits for both-trains of the component 4
Cooling Vater (CCV)-crossover header valves (CC 5095, CC 5096) and the CCV return header from containment valves (CC 5097, CC 5098).-
}
Revised Commitment: Valves CC 5095, CC 5096. CC 5097,-'and CC 5098 vere protected to provide cooling for the Makeup Pumps and the immediate reestablishment of RCP seal cooling and seal return.
CARP Section 4' Note 4 for Fire Area.U (Passage.and Hatch Areas.310 and 313); states i
HPI is the system that is assured for RCS injection (inventory and reactivity control) for safe shutdown. Therefore, the Makeup pumps are not required.
As discussed in item 3 Attachment 2 of this letter, immediate reestablishment of RCP seal cooling and seal return is'no-longer required.. As discussed in Item 2 Attachment.1 of this letter-and in CARP note 4, procedural action is required and adequate time is
.available for manual action.to ensure a letdown path.- Since the valves are not immediately required to achieve hot shutdown and time is available.for manual actions, the fire barrier vraps are not required.
l L:
- 19. Commitment: The SER Table 1, Item B.13' required the installation of a one-half' hour fire rated barrier (Kaovool) in the Service Water Pump Room 52 around the circuits for: the Service Water Pumps (1, 2, 3) and for the Service Water Valves on the' return-line to the forebay-(SV 2930) and the cooling tower makeup (SV 2931).
The Service Water: valve-motors.(SV 2930, 2931) were required to be enclosed with a one-half hour ~ fire rated barrier.
Revised Commitment: CARP Section 4 Note 5 for Fire Area BF (Room 52) states that one of the four SV discharge valves (SV 2929 through SV 2932) is normally open and depovered (controlled administratively) to ensure Service Vater System discharge with a-fire in the area.
CARP Section 4 Note 2 for Fire Area BF states that the Backup Service Water Pump, R
vhich is in Fire Area BD is available as the backup for the three L:
Service Water Pumps b Fire Area BF.
Backup Service Water Pump operation is not af fected by a fire in Fire Area BF.
Therefore, the Kaovool barriers on the conduits for the Service Water Pumps and valves and the Service Water valve motors are no longer required.
't
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- Docket 'Nu;ber 50-346 sr.
'h H Serial Number'l?57 At tachment 3 Page 6
- 20. Commitment: The SER; Table 1, Item B.13 required the installation of a one-half hour fire rated barrier (Kaovool) in the Component Cooling r
Water-(CCW) Pump and Heat Exchanger Room 328 around the circuits for 1
the Component Cooling Water Pumps.1, 2, 3 and the CCV crossover valves (CC SO95, 5096). The underside of the valve motors were also to be s
protected with a one-half hour fire rated barrier.
i Revised Commitment: - Valves CC 5095 and CC 5096 vere protected to provide cooling:for the Makeup Pumps. CARP Section-4 Note 1 for Fire Area T i
(CCW Pump and Heat Exchanger Room 328) states that HPI is.the system that is assured for RCS injection (inventory and reactivity control)
+
for safe shutdown. As discussed in Attachment 1 Item 2 and Attachment J
2 Item 4 of this letter, procedural actions to open/ verify open valves
'CC 5095 and CC 5096'are required to ensure letdown cooling.
Since the i
. valves are not.immediately required to achieve hot shutdown and time
?
is available for manual actions, the fire barrier wraps.are not required.
.The.Kaovool vrap required for the CCW Pump circuits as listed.in CARP Section 4 note 3 is being replaced during the sixth refuel outage with-a one hour fire rated wrap which is more durable than the Kaovool
- vrap.
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I. LDock3t Nu2b2r.50-346
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-Lic ns3 Nu;ber NPF-3 C "'
Serial Number 1757- -
Page.1 Summary of Multiple High Impedance Fault Analysis i
SCOPE j
1' The scope of this analysis is to evaluate the impact of multiple high impedance faults on the essential 480 VAC, 250 VDC, 125 VDC and 120/240 VAC distribution systems.
Equipment operating at voltages greater than 480V is not considered for the following reasons:
a.
There are's relatively limited number of cables operating above 480V, and therefore the cumulative effect of multiple faults vould be limited, b.
'The associated cables are located in diverse areas and are more videly-separated as opposed to their more numerous lov voltage counterparts; therefore, they are less likely to be in the same fire area.
c.
Due to the increased current carrying capability of high voltage power circuits, the deleterious effects of high impedance faults (HIF) are reduced.
ASSUMPTIONS a.
A maximum fault current of 4 amps per affected circuit is assumed. Fault currents greater than 4 amps vill rapidly lead to a bolted fault. This is.
based on ANSI /IEEE standard 242-1986.
Note that the transition to a bolted fault is enhanced by the presence of a fire, making 4 amps a conservative value.-
b.
The high impedance faults occur in-the thermal region of the supply breaker trip characteristic curves, (i.e., expected fault duration and duration to circuit breaker interruption are on the order of minutes).
Motor operated valves are assumed to complete their operation within 30 c.
seconds.
(i.e., they are not a continuously applied load).
d.
Fire conditions exist in only one fire area and other design basis events are not considered.
e.
When AC load information is not available, the value used is equal to 80% of.
the long term trip rating of the nearest upstream feeder breaker. This is consistent with general engineering practice (i.e., see Article 220-10b of the National Electric Code).
f.
Containment lighting is assumed off.
During power operation containment jj lighting is administrative 1y deenergized and tagged out of service as part-of startup procedures. During power operations limited entries are permitted and lighting vill be energized. The frequency and duration of containment entry is sufficiently lov in conjuction with the probability of a fire that no additional action is needed.
a: - -
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- Dock';t.Nurber 50-346-
)
1 Liesns1 Nu2bar NPF-3' 0
Serial Number 1757-Attachment'4
'Page 2 g.
Battery chargers require a 50A supply current.
The 50A value is justified, since most of.the larger DC loads are backup emergency devices which would
- not normally be required when AC power is available, and most of the smaller loads are intermittently operated control circuits.
.h.
Tire in the area of a panel.or MCC is assumed to lead directly to a bolted fault, and result in failure of the associated panel or HCC. This situation falls under the realm of single failure analysis, and is not a subject of this-calculation.
- i. - Unless explicitly stated otherwise, the number of circuits affected by the fire equals the number.of continuously energized circuits passing through the postulated fire area. This results in the highest possible HIF contribution to tne unaffected circuits.-
1
- j. Normal operating loads are considered but not peak or intermittent loads.
-Non-continuous loads are assumed to fall within the 10% margin that exists-on all. power supplies considered, or are enveloped by the higher short-term ratings of the associated supply breaker.
Loads which operate for less than one minute areLeonsidered to be intermittent.
Loads which operate for less-than ten-minutes are assumed to be controlled by operator -judgment and common load management techniques. There are no large scale control signals which cause massive simultaneous actuation of multiple intermittent loads (during this scenario).
k.
HIP currents are only significant at the MCC level or below.
Load centers are not' subject to multiple HIFs.
Basis: The potential HIF current is extremely small in comparison vith the load center current, the associated circuits pass through diverse-fire areas' limiting the total number of circuits' involved in any one fire, and the load centers are coordinated with the MCCs.
1.
Diesel. Generator auxiliaries (e.g. Air Compressors, Start Circuitry, etc.)
(
-are-considered intermittent loads.
1 m.
The several circuits protected by less than a 4 amp fuse have been evaluated
.for their impact. Their effect is not significant in the calculation. A4 amp fault current plus the current load applied to a fuse less than 4 amps will blow the fuse.
The following efficiencies / load factor /pover' factors were assumed for the n.
calculation:
- 1) Power factor of 0.8 was assumed. This is a conservative value which increases the calculated current for loads for which only the kV rating is available.
k
Dockst Nuabar 50-346 i ff Lic nna Nurber NPF '
..C * ' Serial Number 1757~
Page 3 2)- Motor ef ficiency of 80% vas assumed and is based on the " Standard Handbook for Electrical Engineers."
3). An efficiency of 70% is assumed for the static voltage regulators.
METHODOLOGY Total fault current is calculated by multiplying 4A by the number of connected continuous loads passing through the same fire area.
For cases where the fire areas associated with a load are unknown, it is conservatively assumed that the load circuit _ passes through all fire areas.
Bus loading is considered without Motor Operated Valves, since they are only intermittently connected. Total load is determined by adding the continuously-connected loads to the total fault current. The results are evaluated using the acceptance criteria listed below:
a.
The 4 amp high impedance fault postulated for a particular circuit will not cause any overloading, (i.e. the MCC supply breaker long time trip is not exceeded).
b.
The. high impedance faults postulated for a particular circuit cause the first upstream breaker to trip, (i.e. the individual load's supply' breaker opens), or c..
None of the circuits associated with a particular fault which results in breakers opening or fuses blowing are required for safe shutdown.
CONCLUSIONS For the faults defined in the scope above, it is determined that multiple high impedance faults vill not jeopardize the power supply to any load required for safe shutdown.
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Dockat'Nu1ber 50-346-b
- A ~ Lic:nsa Nu;bir NPF-3
' I Serial Number 1757
Attachment:
5' Page 1-Summary of Room Heatup Analysis For Fire Related HVAC Fys lures SCOPE 5
The' scope of this analysis is to evaluate the impact of the loss of ventilation due to damage of electrical circuits caused by fires in the following-areas (as described in Attachment 2 Item 17):
(1)- Fire Area'0 (Room 323)-causing the malfunction of dampers HV 5597 _
(Battery Room 429B Exhaust Fan Damper) and HV 5305 (Lov Voltage Switch Gear Room 429 Exhaust Damper),
(2) Fire Area X (Room 428) causing the malfunction of damper HV 5597 (Battery Room 429B Exhaust Fan Damper); and
.(3)~ Fire Area DD causing the malfunction of dampers HV 5305A and B (Lov-Voltage Switch Gear' Room 429 Intake Dampers).
DESCRIPTION
-The Battery Room 429B is a small room inside the Lov Voltage Switchgear Room (LVSVGR) 429. The Battery Room receives ventilation air from the Lov Voltage Switchgear-Room 429 through a transfer' grill and is exhausted through duct vork s
-by roof-mounted non-sefety-related battery room exhaust fans.
One safety related battery. room ventilation fan is provided to exhaust the room following a
. loss. of of f-site power. The safety related fan motor and exhaust damper HV5597 are supplied from an essential HCC.
The Lov Voltage Svitchgear Room 429 ventilation system consists of a set of non-safety-related supply and return-fans, a safety-related exhaust fan (C71-1),
-two safety-related motor operated outside air dampers (HV5305A and B), a safety-related exhaust damper (HV5305) and associated controls and ductwork.
The normal ventilation system operates to maintain the required temperature.
Safety-related fan is provided to ensure adequate cooling of the room following i
a loss of'off-site power.
ASSUMPTIONS
-1.
As.a result of the fire the plant is manually tripped and a loss of off-siteL power is assumed. The normal ventilation systems are lost and only the safety-related ventilation systems are evaluated.
i 2.- Operator action to reduce the impact of the loss of ventilation in Low-
- Voltage Switchgear Room / Battery Room is assumed to take place after 60 minutes.
3.
This analysis assumes a total loss of ventilation in both LVSVGR and Battery l"
Rooms due to the postulated fire induced damper failures. The room is considered airtight, which maximizes heatup for this calculation.
l 1
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- A Lic:n:o Nu;ber NPF-3 Serial Number 1757
~ Attachment.5 Page 2 4.
At the start of'the transient, outdoor air temperature is 95' F (Design Day) and all other. surrounding interior areas are at 104' F reflecting maximum design plant conditions during summer. The heat sink effect is considered for all LVSVGR Room 429 valls. In addition, the north exterior vall exhibits steady state conduction throughout the transient.
5.
Thermal storage of the steel in the Room 429 is neglected.
- i 6.
For the case under consideration, a conservatively high electrical-equipment heat load of 54KV is assumed to be the maximum steady load during the transient _._ Even certain non-0 loads are assumed to be on without decaying during the transient.
t 7.
For a fire in Room 428 adjacent to 429, the ambient temperature in Room 428 is assumed to go up to 1700'~F instantaneously at start, instead of at 60 minutes, as shown in " Standard Time Temperature curve for control of Fire Tests"-(NFPA 2bl, Appendix B).
This maximizes any potential heat input from Room 428 to Room 429.
CALCULATION PROCEDURE OR ANALYSIS L
A case evaluation was performed for each circuit as described under the scope.-
An overview of each case follows:
Case 1:
A fire in Fire' Area 0 (Room 323) causes damage to the circuits disabling the Lov Voltage Switchgear Room 429 exhaust damper HV 5305 and-the Battery Room 429B exhaust damper-HV5597. The temperature rise in Room 429 is calculated for the
-~54KV load in the room for a period of 60 minutes. The initial room air temperature =and concrete surfaces temperature are both assumed at 104* F, the lL
. maximum 1 esign temperatures. After 60 minutes, the total temperature' difference d
+
t E
between the initial and final room air vill be 17.9' F.
Final air temperatur'e is approximately 122*-F.
The temperature rise in Room 429B is negligible based on the small load in the room.
l' CONCLIISION - Case 1 A review of the equipment in the affected rooms was conducted and concluded that l:
damage to circuits in Fire Area 0 (Room 323)' disabling HV 5305 and HV5597 vil1~
not have any adverse impact for 60 minutes.
After 60 minutes, since dampers HV5305A and HV5305B remain operable and in the open position, portable fans placed in the Room 429 doorway will restore the Room 429 temperature to 104*F.
No further action is required to maintain an acceptable temperature in Room 429B.
-Case 2:
A fire in Fire Area X (Room 428) causing damage to circuit disabling the Battery Room (Room 429B)-exhaust damper HV 5597. The ventilation system performance during this transient is bounded by Case 1 described above since HV5305 is not affected. 'The evaluation included the potential impact of Room 429 temperature due to a fire on the vall between Rooms 428 and 429. Time-temperature profile 1
f or
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' '..Dockst Nu ber.50-346
,j Lic:nst Nu ber NPF-3 1
Serial 1 Number 1757.
4
. Attachment 5.
Page 3 calculations;vith conservative fire temperature assumptions indicates that at'60 minutes, the temperature effects from the fire are felt only approximately halfway through the concrete vall, leaving the Room 429 temperature unaffected
.by the fire.
CONCLUSION - Case 2 It is concluded that there is no additional heat input into Room 429 resulting from'a fire in Room 428. The safety-related ventilation system for LVSVGR Room 429 is fully operational. No action is required to maintain an acceptable temperature cfther in Room 429 or Room.429B, i
Case 3:
A fire in Fire Area DD (Room 422A> causing damage to circuits disabling the LVSVGR 429. intake dampers HV5305A and HV5305B. This case is the same-as Case 1 except'the exhaust damper remains open to allow hot air to exit.
Since the exhaust fan-vill be' operating and exhaust damper HV5305 vill remain open, the peak room temperature reached during the fire transient vill be lower than that in the Case 1 analysis.
CONCLUSION - Case 3 1
Based on the above,.no further analysis is needed and the conclusions reached in Case 1 are conservative. After 60 minutes, the intake damper HV 5305B being opened in conjunction with the exhaust fan operating and the exhaust damper open
'vi11' restore the Room 429 temperature to 104'F.
p
SUMMARY
Based-on the evaluation of the three cases involving fires in Rooms 323, 428 and 422A' disabling various combinations of dampers HV5597, HV5305, HV5305A and HV5305B, it is concluded that:
a).
The temperature transients experienced during the fire vill not prevent the operation of equipment in the LVSVGR Room 429 and Battery Room 429B. The limiting equipment required for safe-shutdown in the rooms has been shovn' to be functional for one hour at an elevated room temperature of 122*F.
b).
The circuits controlling the above list of dampers are not required to be protected.
c).
Manual actions to open the door to Room 429 and to install portable fans or i
to open the intake damper HV 5305B are required within 60 minutes.to restore Room 429 temperature to 104'F.
No manual action is required in Room 429B.
.